The amount of energy transmitted by an electronic component into a board on which the component is mounted can affect the board's and the component's performance. The energy generated by the component is a function of the construction material of the component, the material used in the board and the thermoconductivity of the component and the board. Other factors affecting the component or the board's temperature include air velocity and availability of a cooling system. Determining the amount of energy transmitted by a component into its surrounding is complex and time consuming. Such determinations are often necessary for the design of the system and require sophisticated software systems and hours of calculation. Such software typically utilize finite element analysis (FEA).
A typical calculation determines the component's temperature as a function of its construction material and the heat generated when the component is operating continuously at its maximum capacity. Under such conditions, the thermal profile of the component under study is typified by a curve having a rather steep initial slope which gradually approaches an asymptotic point. The temperature remains constant beyond the asymptotic point. Consequently, the asymptotic point can be viewed as the point where the device reaches its steady state temperature. That is, the point at which further rise in temperature and heat loss due to cooling reach an equilibrium.
Depending on the complexities of the component, the conventional models require up to several hours for determining the component's steady state temperature. If the component is operated intermittently or if the component is used at less than its maximum capacity, the conventional systems typically fail to predict a steady state temperature. Using FEA for thermal analysis of such systems can take up to several days if not weeks of calculation. Accordingly, there is a need for a method and apparatus for predicting the steady state temperature of a solid state device during transient operation.